The present invention relates to a shirred tubular casing having both a main fold and accessory fold structure, to a shirring member used for manufacturing the shirred tubular casing, and to an apparatus which includes the shirring member for manufacturing the shirred casing.
A shirred tubular casing, also referred to as shirred stick, of this general type is disclosed in U.S. Pat. No. 3,907,003. Similarly, a shirring member and an apparatus equipped with this shirring member are known from U.S. Pat. No. 4,185,358. The previously disclosed shirred stick is very densely shirred, which is an advantage in view of its resistance to bending, but may prove a severe disadvantage when soaking the shirred stick in water prior to the filling operation. It is, for example, necessary to soak these shirred sticks for extended time periods; however, the extended soakings may result in the sticks absorbing water non-uniformly. These disadvantages occur, above all, in tubular casings comprising fiber-reinforced regenerated cellulose.